The retention time (trtr) and peak width (ww) for compounds a and b are given after chromatographic separation using five different experimental parameters.

which chromatographic separations achieved a resolution that is desirable for quantitative analysis?

separation 1:
compound a: tr=15.0 min; w=5.0 min
compound b: tr=17.0 min; w=6.5

separation 2:
compound a: tr=11.0 min; w=3.0 min
compound b: tr=19.0 min; w=3.0 min

separation 3:
compound a: tr=11.0 min; w=4.0 min
compound b: tr=16.0 min; w=5.0 min

separation 4:
compound a: tr=10.0 min; w=2.0 min
compound b: tr=16.0 min; w=3.0 min

separation 5:
compound a: tr=11.0 min; w=2.5 min
compound b: tr=14.0 min; w=4.5 min